If you need support from Yola please contact us via firstname.lastname@example.org or make use of our live chat service! We are working on a new approach to community-based support and during this transition period we are not adding any new threads to this forum. Many thanks to everyone who has participated over the years and we look forward to unveiling a new peer-to-peer support system soon!
Yes, like Marije says, you can definitely update your site anytime you want to.
Once you've published your site the first time, you'll notice that the big, yellow "Publish My Site" button turns into an "Update My Site" button. If you click on that your site will be updated with any changes you've just made (this is the same as the "Republish" action).
Clicking the little arrow next to "Update My Site" will show you some additional publishing options, like managing tags and domain names.